Effect of multivitamins on plasma homocysteine and folate levels in patients on hemodialysis

Abstract

Hyperhomocysteinemia is a risk factor for cardiovascular disease in patients on hemodialysis. Causes include genetic enzyme deficiencies, chronic renal failure, and vitamin deficiencies. Homocysteine correlates negatively with folate status. In patients on hemodialysis, supraphysiologic doses of B vitamins and folate reduce homocysteine by 26-33%. No study has examined the effect of a standard multivitamin (Nephro-Vite Rx), containing B vitamins and 1 mg of folate, on erythrocyte-folate (RBC-folate) and homocysteine in patients on dialysis. We examined RBC-folate and homocysteine levels in 11 stable chronic patients on hemodialysis, mean duration of dialysis 9.8+/-4.1 months, who were not on vitamin or folate supplements, and repeated these levels after 3 weeks of once daily Nephro-Vite Rx dosage. Plasma homocysteine levels fell by 23.7% from 27.8+/-5.9 to 21.2+/-6.6 micromol/L (p = 0.007), whereas RBC-folate levels rose 60% from 631.2+/-208.3 to 1007.5+/-423.7 nmol/L (p = 0.001). The optimum dose of B vitamins and folate remains to be established, and a clinical benefit from lowering homocysteine has not yet been demonstrated. In summary, a standard multivitamin such as Nephro-Vite Rx reduces plasma homocysteine levels and increases RBC-folate levels in patients on hemodialysis. Our results may have implications for the modification of cardiovascular risk in these patients.